Trends in the treatment of acute myeloid leukaemia in the elderly

Abstract

Introduction: Acute myeloid leukaemia (AML) is the most common type of leukaemia among adults in the US. However, data on longitudinal treatment patterns and outcomes associated with AML and its relapse are sparse, particularly among the elderly. This study documents changes in treatment patterns and outcomes among elderly AML patients over the past decade.

Methods: Using the linked Surveillance, Epidemiology, and End Results (SEER)-Medicare database, we retrospectively evaluated trends in mortality, treatment patterns, healthcare resource utilisation and Medicare payments associated with AML and its relapse among Medicare beneficiaries > or =65 years of age who were initially diagnosed with AML in a SEER registry between 1991 and 1999. Chemotherapy was ascertained from examination of inpatient and outpatient bills. AML relapse and retreatment were identified using a validated algorithm. Costs of care were based on total Medicare payments.

Results: A total of 3439 elderly patients with AML were identified. Median survival across all study patients was 2.4 months (mean +/- SD 5.6 +/- 6.8 months), with medians of 3.9, 2.2 and 1.4 months for patients 65-74 years of age, 75-84 years of age and > or =85 years of age, respectively. Fewer than 7% of patients were alive at 2 years, and there was very little variation during the decade of our analysis. Costs and overall healthcare utilisation patterns also changed very little, with the exception of those relating to hospice use and chemotherapy. Hospice use more than doubled during the decade (from 12% to 29% among patients diagnosed in 1991 and 1999, respectively; p < 0.0001), mostly among the oldest patients. Administration of chemotherapy also increased from 29% of patients diagnosed in 1991 to 38% of patients diagnosed in 1999 (p = 0.014), with the increase being seen mostly among younger patients and those treated in teaching hospitals. Average total costs (+/- SD) were US$51,888 +/- $54,825 and declined by age as a result of lower survival. A total of 192 patients (16% of treated patients) relapsed and received retreatment with chemotherapy. These patients survived a median 18 months, with a median duration of remission of 8 months, and average total costs three times higher than the overall sample.

Conclusions: The high early mortality and costs associated with AML have not changed significantly over the past decade. However, treatment patterns appear to be changing, with increasing use of chemotherapy and hospice care. The ongoing introduction of new treatments for AML in the elderly is likely to further impact treatment patterns, and may change the economic burden of the disease. Our findings can be used as a baseline against which the benefits of new therapies can be compared.